Properties and Biological Performance of Glass-ionomer Cement Modified by Bioactive Glass Nanoparticles

Objectives: The objective of this study was to assess the addition of nanoparticles bioactive glasses (NBG) into glass ionomer cement (GICs).
Methods: NBG of 70% SiO₂–30% CaO (mol%) composition was prepared by sol-gel chemistry and characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). NBG were incorporated into the powder of GIC (Fuji II LC, GC Corp, Tokyo, Japan) at 0%, 3%, 5%, 10%, 15% and 20% (w/w). Glass ionomer-Bioactive glass (GIBG) specimens (n=10/group) were prepared based on ISO standards and subjected to a three-point bending test in a universal testing machine. Surface hardness was measured using Vickers microhardness tester. Murine-derived osteoblastic cells (MC3T3-E1) were seeded onto GIBG discs to assess the cell attachment and cell viability for 24 hours and characterized by SEM and MTS assay (Promega, Madison, WI, USA). The data were statistically analyzed.
Results: The GIC containing 3% and 5% (w/w) NBG (GIBG3 and GIBG5) exhibited higher flexural strength when compared to other groups (significant at p<0.05). Data for surface microhardness showed reduction in hardness number with increasing concentration of NBG incorporated. In vitro cell biocompatibility showed attachment of cells onto GIBG samples. Cell viability showed increased numbers of cells with increasing concentrations of NBG.
Conclusions: It is believed that the ions released from the BGs play significant roles in stimulating cell growth and differentiation.